Bulk container



May 25, 1965 F. A. KOHLHAAS BULK CONTAINER 2 Sheets-Sheet 1 Filed May 21, 1965 INVENTOR:

F. A. KOHLHAAS WWW AGENT May 25,- 1965 F. A. KOHLHAAS 2 Sheets-Shet 2 BULK CONTAINER Filed May 21, 1963 INVENTOR:

EA. KUHLl/AAS AGENT United States Patent 3,185,379 BULK CONTAINER Frank ,A. Kohlhaas, Minneapolis, Minn., ElSSlgllOl to Crown Zellerbach Corporation, San Francisco, Calif., a corporation of Nevada Filed May 21, 1963, Ser. No. 281,882 4 Claims. (Cl. 229-23) This invention relates to heavy duty bulk containers and a package for individually frozen food products and other materials having a flow characteristic and which exert outward pressure on the container walls. More particularly the invention provides a bulk container of comparison to prior packaging and materials handling methods, there is a constant effort to develop such fibreboard containers affording further advantages such as reduced materials, ease of assembly, adaptability to reuse and the like. Further it is desired that such containers exhibit improved strength characteristics such as resistance to bulging or distortion, ability to stack in vertical columns and provide improved protection for the specific requirements of various products that may be packed therein.

While it is obvious that bulk containers may be strengthened by using heavier weights of paperboard materials or by adding additional reinforcing means such as added rigidifying panels, reinforcing bands, and the like, it is desirable to rigidify these bulk containers while economizing on materials. This necessitates a high order of invention to provide a container wherein high strength characteristics are attained through the very efficient use of lighter weights of fibreboard materials and minimal amounts or square footage of such materials but in a precise manner to attain unusual cooperative and reinforcing characteristics of the structural elements of the container and an unusually high degree of efficiency.

For example, a common and successful bulk container unit has been used wherein the vertical walls of the container are constructed of telescoping inner and outer sleeves in closely fitted relationship, such containers commonly have telescoping end caps or trays which closely fit about the top and bottom marginal edges of the sleeves to close the container and to assist in resisting bulging of the medial portions of the ends of the wall panels. As such containers have been used for ever increasing larger amounts of flowable materials, they have required additional reinforcing means such as the addition of integral end flaps or flanges.

which are infolded in perpendicular relation to the container walls and in flatwise relation to the interior surfaces of the central panel of the end closure caps. This expediency has markedly increased rigidity as fibreboard and other usual types of foldable panel materials acquire their greatest rigidity at corner folds which provide mutual reinforcing of adjacent panel areas on either side of such fold lines. This structural arrangement, while it has met with considerable commercial application, has not been fully satisfactory as additional footage of fibreboard is required and the assembly procedure is additionally complicated by the necessary manipulation of the reinforcing flaps.

In contrast to the preceding, the present invention provides a simplified construction which requires a lesser footage of fibreboard materials and in commercial utilization thereof has demonstrated an ability to equal or exceed the strength characteristics of the prior art containers even with lighter weights of fibreboard materials as well as lesser amounts thereof. In its basic aspect, the present invention is characterized as a large heavy duty container for bulk pack commodities having a flow characteristic and exerting outward pressure tending to distend the container walls. The container comprises paired tubular sleeves in side by side relation and telescoping end closure caps unitizing the sleeves. The sleeves are each of rectangular tubularly arranged panel formation with the panels foldably connected by vertical corner scores and including a pair of panels secured together in coextensive overlapping relation with the pair of overlapping panels of each sleeve forming respectively the transverse end walls of the container. A medial transverse wall of the container is comprised of the confronting coextensive panels of the paired sleeves. The longitudinal side wall of the container, having the major dimension and normally being subject to maximum distention or distortion, is reinforced by the fold connection of the transverse medial walls to the mid-point of the longitudinal wall of the container; so that, the single thickness panels of the sleeves, which in linearly aligned paired relationship compris the longitudinal container walls, are of minimal extent and of less horizontal width dimension than the double thickness reinforced container transverse end or medial walls.

These and other objects and advantages of the invention will be apparent to those skilled in the art upon a full and complete understanding of the construction and operation of this container as exemplified in the followmg detailed description wherein the invention consists in the parts, arrangements and combinations hereinafter described and claimed. The accompanying drawings form a part of this specification and like numerals and symbols therein appearing refer to like parts wherever they occur.

In the drawings: FIGURE 1 is an exploded perspective view showing a preferred form of the present invention;

FIGURE 2 is an exploded perspective view, with parts broken away, showing a prior art container for similar utilization;

FIGURE 3 is a plan view of the blank for forming an end closure cap;

FIGURE 4 is a plan view of a blank for forming an alternative end closure cap;

FIGURE 5 is a partial cross-section through line 5--5 of FIGURE 1;

FIGURE 6 is a perspective view of a container embodying the invention partially filled with flowable materials and positioned on a pallet;

FIGURE 7 is a perspective view of the container in fully assembled condition and secured to a pallet.

The containers for bulk commodities as in the present invention are necessarily handled by mechanical means as they commonly are of a capacity to hold 1200 to 1500 pounds of loose fiowable materials. monly positioned on pallets to facilitate entrance of the lifting elements of fork lift trucks. It is highly desirable that containers of this nature conform to certain norms of lateral dimension and there is actually concerted effort to establish standardized pallet sizes to facilitate ship- Thus they are com- 7 ment and handling of such containers. A desirable standardized pallet dimension is 40x48 inches as containers and pallets conforming to these dimensions will accommodate themselves readily to loading arrangements both in standard truck and railroad freight car carriers.

The present invention is particularly accommodated to these rectangular proportions and more generally speaking is accommodated to rectangular proportions wherein the transverse width dimension is less than but in excess of one-half the longitudinal length dimension.

In these rectangular proportions the container shown in FIGURE 1 provides a precise arrangement of double thickness transverse walls and single thickness longitudinal container walls which are advantageously arranged and proportioned to maximize the rigidifying effects of corner folds and minimizing lateral extent of the single thickness non-reinforced panels whereby maximum strength characteristics are realized while maintaining economical levels of board utilization both in regard to footage and weights of materials.

The container indicated generally at 20 in FIGURE 1 comprises paired tubular sleeves 21-22 which each comprise confronting panels 23 and opposed double thickness transverse end walls 24 having inner panels 25 and outer panels 26 in coextensive overlapping relation. The inner panels 25 and outer panels 26 in each respective pair are secured together as by a line of stitches 27 which are arranged adjacent to the outer panels 26 free side edges 28 and end corner folds 30. The inner panels 25 free side edges 29 are disposed adjacent the interior of end corner folds 30.

The other single thickness walls 31 of the sleeves 21-22 are in respective paired aligned relationship forming the container longitudinal walls and are foldably connected to the confronting panels 23 by the medial corner folds 34.

The top ends 32 of the tubular sleeves 21-22 are determined by the free upper edge of the sleeve panels and are in coplanar horizontal relation. The bottom ends 33 of the sleeves 21-22 are likewise determined by the free end edges of the sleeve wall panels.

The top and bottom closure caps 40-41 respectively may be of similar construction as shown and each comprises a central panel 42 coextensive to the combined dimensions of the ends of the tubular sleeves 21-22 and depending end flanges 43 and side flanges 44 which form depending walls adapted to telescope about the outer surface of the end portions of the sleeves 21-22 and closely engage the same to unitize the sleeves into cooperative relationship.

The end caps 40-41 may be constructed from a blank as shown in FIGURE 3 wherein the central panel 42 is defined by end scores 46 and side edge scores 47. The end flanges 43 are comprised of outer and inner flaps 48- 49 in foldably connected relation to each other and to the central panel 42. The side flanges 44 are likewise comprised of foldably connected outer and inner flaps 50-51 in foldably connected relation. Corner connecting flaps 52 are foldably connected to the ends of the side flanges 44 inner and outer flaps 50-51. The corner connecting flaps are separated from the end flange 43 by slots 53 and may each be further divided by a slot 54 into outer and inner plies corresponding to the outer and inner plies 50-51 of the side flange 44.

To assemble the blank of FIGURE 3 to form a top or bottom end cap 4tl-41 the inner flaps 51 are folded into flatwise relation with the outer flaps 50 and the thus formed side flanges or walls 44 are folded into perpendicular relation to the central panel 42. Thereupon, the corner connecting flaps 52 are folded perpendicularly into parallel relation with the end scores 46. Finally the end flanges 43 are folded upwardly and about the corner connecting flaps 52 and frictionally engaged or engaged by the use of suitable locking devices as are known in the art to complete the assembly of the cap. It is to be noted that this construction may be manually assembled and disassembled for shipment and reuse if desired.

An alternative end cap construction is disclosed in FIGURE 4 wherein the blank comprises a central panel 42' which is determined by end scores 46 and side scores 47'. These side scores 47' may be in the form of double lines of scoring as shown to facilitate the collapsing feature of this construction. The end flanges 43' include end scores 56 and angular collapsing scores 57. The triangular form corner connecting flaps 58 are separated from the corresponding side flange 44' triangular corner connecting flaps 59 by bisecting cut lines 69. The triangular corner connecting flaps 59 are foldably connected to the ends of the side flanges 44'. The outer apexes of the triangular corner connecting flaps 58-59 are preferably foreshortened as by the arcuate cut edges 61 as shown to minimize possible projection of these apexes in the erected condition of the cap.

To erect the collapsible lid formed from the blank of FIGURE 4 the end and side flanges 43'-44 are folded into perpendicular relation to the central panel 42 and the corner connecting flaps 58 secured to the inner surface of the end portions of the side flanges 44 and the triangular corner connecting flaps 59 secured to the outer surface of the end flanges 43' portion determined between the end scores 56 and angular collapsing scores 57. The resulting cap can then be collapsed for storage or shipment by infolding the side flanges 44' into overlying relation with the side margins of the central panel 42' while folding the end flanges 43' outwardly about the collapsing scores 57.

In FIGURE 5 there is shown a cross-sectional view through line 5-5 of FIGURE 1. It is to be noted that the sleeves 21-22 are preferably formed from double wall corrugated board which comprises facing sheets 65 and intermediate liners 66 which are separated by corrugated plies 67. The stitch joint 27 is readily embedded in the overlapping thickness of the double wall board at the manufacturers joint as shown so that the interior surface 68 of the sleeves is free of substantial projections which might tend to mar or abrade any liners or interior treatment of the container which may be required for specific products to be packaged in the container.

A partially erected and filled container is shown in FIG- URE 6 wherein the bottom cap 41 is positioned upon a pallet 70. The tubular sleeves 21-22 are positioned within the side and end flanges 43-44 of the end cap so that the bottom ends 33 of the sleeves rest upon the interior surfaces of the central panel 42 which may be determined by reference to the exploded view in FIGURE 1. Each tubular sleeve 21-22 forms a compartment in the container which may be filled with a flowable commodity as for example individually quick frozen vegetables 71 which are included in polyethylene bags 72 or liners to keep the product out of contact with the container interior wall surfaces and thus permit reuse of the container and further to eliminate dehydration of the product.

The completed container is shown in FIGURE 7 wherein the top end cap 40 has been positioned in telescoping relation with the top margins of the tubular sleeves 21-22 so that the top ends of the sleeves 32 (not shown) are in abutting relation with the interior surfaces of the end cap central panel 42. In order to secure the container assembly together and to the pallet, a band 73 may be secured thereabout as shown wherein the band is preferably disposed medially of the transverse end walls 24 of the sleeves.

The invention has been particularly successful in a specific commercial utilization for individually frozen vegetables which have a free flow characteristic and tend to exert outward pressure on the container walls. In prior art devices, as shown in FIGURE 2, which have been used for this same commercial application, it has been necessary to use very heavy Weights of fibreboard to resist such distention and the conventional construction additionally requires greater footage of corrugated board for the container. For example, in FIGURE 2 is shown an exploded view of a container 80 which comprises a bottom cap 82 and inner and outer sleeves 83-84. The inner and outer sleeves are in closely fitting slidable relation to provide mutual reinforcement. A similar top closure cap 81 is disposed in telescoping relation about the top margins of the container walls. It is to be noted that in the commercial sizes for such containers each of the sleeves must normally be constructed in two pieces having paired manufacturers joints 8586 in the inner sleeve 83 and similar paired manufacturers joints 87-88 in the outer sleeve 84. To additionally reinforce the considerable lateral extent of each of the container walls, it has been found necessary to provide integral hinged reinforcing flanges 89 which are hingedly connected to the top and bottom edges of the outer sleeve 84. Of course, equivalent alternative arrangements are possible wherein bottom reinforcing flanges (not shown) may be connected to the bottom edges of the inner sleeve 83. It is evident that the footage of corrugated board in this construction substantially exceeds that required for the identically sized and proportioned container of the present invention in the specified desirable proportions which conform to the standard pallet dimension. Additionally, commercial experience has shown that the prior art construction has required the use of higher tests and heavier weights of corrugated board than the present invention and even then stacking such container has not been completely satisfactory particularly if the vertical walls are not perfectly aligned vertically in the stacks.

It is to be understood that the embodiments herein described are illustrative and not restrictive, and it is also to be understood that the invention may be susceptible of embodiment in other modified forms and that all such modifications which are similar or equivalent hereto come equally within the scope of the claims next appearing.

In the claims:

1. A large heavy duty paperboard container for bulk pack commodities having a flow characteristic and exerting outward pressure tending to distend the container walls, the container being of a size and weight with the commodity to require mechanical handling means and having single panel thickness, major longitudinal walls and double panel thickness smaller transverse walls which are more than one-half the longitudinal wall dimension of the container, the container comprising paired tubular sleeves in side by side relation and telescoping end closure means unitizing the sleeves, the sleeves each being of rectangular tubularly arranged panel formation with the panels thereof foldably connected by vertical corner scores and including a pair of said panels in secured together coextensive overlapping relation, said paired overlapping panels of each sleeve forming respectively container transverse end walls, a medial transverse wall of the container comprised of confronting coextensive panels of the paired sleeves, the major longitudinal side walls of the container being comprised of the remaining single thickness panels of the sleeves in respective paired aligned relationship, said single thickness panels each being of less width than the double thickness reinforced container transverse and medial walls and being restrained against outward distension by the fold connections to the transverse end and medial walls.

2. A large heavy duty paperboard container for bulk pack commodities having a flow characteristic and exerting outward pressure tending to distend the container walls, the container being of a size and weight with the commodity to require mechanical handling means and being of rectangular conformation having single panel thickness, major longitudinal walls and double panel thickness, smaller transverse Walls which are more than one-half the longitudinal wall dimension of the containers, the container comprising paired tubular open ended sleeves in side by side relation and telescoping end closure means unitizing the sleeves, the end closure means comprising top and bottom caps with depending walls, the cap walls enclosing the respective end portions of the sleeves and being of less vertical height than the sleeves, the sleeves each being of rectangular tubularly arranged panel formation with the panels thereof foldably connected by vertical corner scores and having top and bottom end edges, said sleeves each including a pair of said panels in secured together coextensive overlapping relation, said paired overlapping panels of each sleeve forming respectively container transverse end walls, a medial transverse wall of the container comprised of confronting coextensive panels of the paired sleeves, longitudinal side walls of the container comprised of the remaining single thickness panels of the sleeves in respective paired aligned relationship, said single thickness panels each being of less width than the double thickness reinforced container transverse and medial walls and being restrained against outward distension by the fold connections to the transverse end and medial walls.

3. A collapsible large heavy duty paperboard container for bulk pack commodities having a flow characteristic and exerting outward pressure tending to distend the container walls, the container being of a size and weight with the commodity to require mechanical handling means and being of rectangular conformation having single panel thickness, major longitudinal walls and double panel thickness, smaller transverse walls which are more than one-half the longitudinal wall dimension of the containers, the container comprising paired tubular sleeves in side by, side relation and telescoping end closure means unitizing the sleeves, the end closure means comprising top and bottom caps each having a central panel with foldably connected flanges thereabout forming depending walls, the cap walls enclosing the respective end portions of the sleeves and being of less vertical height than the sleeves, the sleeves each being of rectangular tubularly arranged panel formation with the panels thereof foldably connected by vertical corner scores and having top and bottom end edges abutting the interior surface of the respective end cap central panel, said sleeves each including a pair of said panels in secured together coextensive overlapping relation, said paired overlapping panels of each sleeve forming respectively container transverse end walls, a medial transverse wall of the container comprised of confronting coextensive panels of the paired sleeves, longitudinal side walls of the container comprised of the remaining single thickness panels of the sleeve in respective paired aligned relationship, said single thickness panels being of less width than the double thickness reinforced container transverse and medial walls, the single thickness longitudinal side walls of the container being restrained against outward distention by the fold connections to the transverse end and medial Walls and the depending walls of the end caps about the top and bottom end portions thereof.

4. A package for bulk packed individually frozen food products or the like having a flow characteristic and exerting outward pressure tending to distend the container walls, the package being of a size and weight to require mechanical handling means and including a large heavy duty paperboard container positioned on a pallet, the container having single panel thickness major longitudinal walls and double panel thickness smaller transverse walls which are more than one-half the longitudinal wall dimension of the container, the container comprising paired tubular open ended sleeves in side by side relation, end closure means unitizing the sleeves, and a liner within each sleeve enclosing the product, the end closure means comprising top and bottom caps with depending walls, the cap walls enclosing the respective end portions of the sleeves and being of less vertical height than the sleeves, the sleeves each being of rectangular tubularly arranged panel formation with the panels thereof foldably connected by vertical corner scores and including a pair of said panels in secured together coextensive overlapping relation, said paired overlapping panels of each sleeve forming respectively container transverse end walls, a

medial transverse wall of the container comprised of con fronting coextensive panels of the paired sleeves, longitudinal side walls of the container comprised of the remaining single thickness panels of the sleeves in respective paired aligned relationship, said single thickness panels each being of less width than the double thickness reinforced container transverse end and medial walls and being restrained against outward distention by the fold connections to the transverse end and medial walls and the depending walls of the end caps about the top and bottom end portions thereof.

References Cited by the Examiner UNITED STATES PATENTS Surman 229-23 Walter 229-23 X Belsinger 229-23 Murray 229-23 Belsinger 229-23 X Budd 229-29 X Neuman 229-23 X Lawrence 229-23 Winstead 229-14 X Vail 229-23 Wilson 229-15 15 FRANKLIN T. GARRETT, Primary Examiner. 

1. A LARGE HEAVY DUTY PAPERBOARD CONTAINER FOR BULK PACK COMMODITIES HAVING A FLOW CHARACTERISTIC AND EXERTING OUTWARD PRESSURE TENDING TO DISTENT THE CONTAINER WALLS, THE CONTAINER BEING OF A SIZE AND WEIGHT WITH THE COMMODITY TO REQUIRE MECHANICAL HANDLING MEANS AND HAVING SINGLE PANEL THICKNESS, MAJOR LONGITUDINAL WALLS AND DOUBLE PANEL THICKNESS SMALLER TRANSVERSE WALLS WHICH ARE MORE THAN ONE-HALF THE LONGITUDINAL WALL DIMENSION OF THE CONTAINER, THE CONTAINER COMPRISING PAIRED TUBULAR SLEEVES IN SIDE BY SIDE RELATION AND TELESCOPING END CLOSURE MEANS UNITIZING THE SLEEVES, THE SLEEVES EACH BEING OF RECTANGULAR TUBULARLY ARRANGED PANEL FORMATION WITH THE PANELS THEREOF FOLDABLY CONNECTED BY VERTICAL CORNER SCORES AND INCLUDING A PAIR OF SAID PANELS IN SECURED TOGETHER COEXTENSIVE OVERLAPPING RELATION, SAID PAIRED OVERLAPPING PANELS OF EACH SLEEVE FORMING RESPECTIVELY CONTAINER TRANSVERSE END WALLS, A MEDIAL TRANSVERSE WALL OF THE CONTAINER COMPRISED OF CONFRONTING COEXTENSIVE PANELS OF THE PAIRED SLEEVES, THE MAJOR LONGITUDINAL SIDE WALLS OF THE CONTAINER BEING COMPRISED OF THE REMAINING SINGLE THICKNESS PANELS OF THE SLEEVES IN RESPECTIVE PAIRED ALIGNED RELATIONSHIP, SAID SINGLE THICKNESS PANELS EACH BEING OF LESS WIDTH THAN THE DOUBLE THICKNESS REINFORCED CONTAINER TRANSVERSE AND MEDIAL WALLS AND BEING RESTRAINED AGAINST OUTWARD DISTENSION BY THE FOLD CONNECTIONS TO THE TRANSVERSE END AND MEDIAL WALLS. 